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KentuckyFC writes "Metamaterials are synthetic substances that can steer light in any way imaginable. Their most famous incarnation is in invisibility cloaks which work by steering light around a region of space making any object inside that region invisible. But invisibility is just the start. A team of physicists in Hong Kong (the same guys who recently worked out how to cloak objects at a distance) have worked out how to create a cloak that makes one object look like another. Instead of steering light to make a region of space look empty, the illusion cloak manipulates light in a way that makes a region of space look as if it contains a specific object. So any object within that region of space, a mouse say, takes on the appearance of an elephant."

Instead of steering light to make a region of space look empty, the illusion cloak manipulates light in a way that makes a region of space look as if it contains a specific object, such as an elephant. So any object within that region of space, a mouse say, takes on the appearance of an elephant."

This is just going to piss off astronomers and give more credence to the UFO and ET enthusiasts when miscreants start projecting images of elephants floating around in the night sky.

When I moved to a new apartment in Chicago's New Town in my early twenties, my roommate (native of Kansas) and I walked around the corner to get a beer after a long day of hauling furniture. The first thing we noticed was the place was full of incredibly hot girls.

Or so we thought...

Fortunately, a bartender took pity on us two naifs and clued us in before we did anything irredeemable. My buddy, who was a few beers ahead of me, took some convincing, let me tell you.

Cognitive dissonance, when it involves the little head, is tough to deal with sometimes.

In your scenario, someone makes a lot of money selling some magical mystical shit. In my scenario, they could probably just use fitted covers (maybe with mylar in them so they show up on radar too) with a nice four-color job on them and someone gets to pocket the savings. I guess either way the taxpayer loses.

But the ammunition will be different. When you see a truck, you hit it with High Explosive (HE) or heavy machine gun fire. If you see a tank, you hit it with Kinetic Energy (KE) or High Explosive Anti-Tank (HEAT) rounds.

There is good reason for this. If you hit a tank with something that just explodes and rains shrapnel, the hit will just bounce off, maybe destroying the optics but that is about it. You have to pierce the armor, which you do by hitting it with something very heavy and slender (such as a rod of depleted uranium) traveling at high speed that focuses a bunch of energy on one point. The heat from the collision and spalling from the armor itself then destroys whatever is behind the armor.

This does not work for a truck. If you hit it with a KE round, the round will just sail right through it. If there is nothing vital (the driver, engine, fuel lines, etc) where the KE round happens to pass, then the truck will just keep rolling. That is why you hit it with HE or MG fire. The many small bits of metal from an exploding HE round have a much higher chance of hitting something vital than the single big chunk from a KE round.

As far as a tank is concerned, you usually only get one or two shots at it before it or its buddies start returning fire. If you hit it with the wrong ammunition, he is going to kill you.

It should be noted that the inverse is also true. Making vehicles such as a truck look highly armored increases their survivability in certain situations because AT rounds are rarer than lighter ammunition and an infantry squad with a machine gun is not going attack a tank.

Isn't it easier, and cheaper, to just have Dick Cheney "supervise" the people collecting data, and help them provide "enhanced" photos for the UN?

Colin Powell's presentation of those smudgey, awful, inaccurate photos to the USA was also a great way for the Republicans to make sure they didn't have to deal with a black candidate from their own party: you could see his career nosediving along with the respect for the US every day as that mess progressed.

Why make a tank look like a heavy truck or a rocket launcher look like a stack of pipes when you could make them look like just another rock?

a rock? i was thinking more along the lines of making the tank look like a tree, and loading it up with armor piercing shells. combine a few of those with some prism tanks, and the only thing to worry about are soviet blimps.

I'd prefer to make a tank look like a Volkswagen beetle. just imagine the field of battle, a swarm of beetle against beetle firing tank shells at one another
"Sarge it looks like they're bringing out the heavy artillery, I can spot 3 Ford Escorts's and what looks like postman pat's van in the distance"

It'd be great as a car alarm / defense system, one click of a button and the car changes from a Ferrari into a Robin Reliant (let's face it no-one's going to steal one of those)

Imagine the ability to make a tank look like a heavy truck at a distance(say to a drone)

While that may work really well with people and detection systems that depend on light, it's probably worth pointing out that these metamaterials will probably have little affect on other methods of detection, such as radar and infrared, for example.

Metamaterials are synthetic substances that can steer light in any way imaginable

As I understand it, Drones have do have infrared cameras (as an example). Of course, that doesn't make much difference if the ground pilot is navigating entirely by the visible light camera and has to switch modes or something, but I'm not really sure how that

If I remember correctly the invisibility cloak that exists (how strange to write that) is for the infrared spectrum. Visible light may be harder because the range is broader, or I could be way off base. It's a gamble!

Fiddle with an invisibility cloak, and it can make any object look like another, say researchers.

Great! This is awesome. Now, where did I put my invisibility cloak so I can fiddle with it?

The researchers have even found a mind-boggling application. Their idea is to create the illusion that a wall has a hole in it, and then use the hole to look through the wall.

That's not quite as bonkers as it sounds. The wall has to be pretty thin, and what the new device does is allow light to tunnel through the wall in a way that would not ordinarily be possible. Amazing, if it works.

Yes, the wall must be thin -- thin enough for light to pass through it. In other words, thin enough to see through without the cloak on top of it. So, in order to see through a see-through wall, we put the cloak in front of it, then make the cloak appear to be a hole, through which we can see through the see-through wall. I see.

These gedanken experiments are nice and all, but I'll believe it when I see it. Or rather, when I don't.

hmm.. those thin walls with invisibility cloaked holes... I think I have a name for them : "Windows" (and I'm not refering to the operating system whose makers equate transparency with communism by the way)

You can bet your invisible boots that if the Emperor's New Clothes had (while obviously only being visible to "very wise people") nonetheless kept the Emperor warm and dry, that story would have ended differently. Probably with research into military applications.

I hate all these cloaking articles they give really great 'examples' of what could be done with such technology but the actual news is much more mundane. In fact from the small freaking article it seems they have a math proof probably not even a prototype yet.

In fact from the small freaking article it seems they have a math proof probably not even a prototype yet.

What makes you think there are no prototypes yet? Just because they didn't show you photos? If you were in the military, wouldn't you fly out to see these guys ASAP when you heard this? Would you give them large amounts of cash if it looked probable? Would you keep a very tight lid on any prototypes that they produced?

I am not a believer in conspiracy theories, but I would be very disappointed in

That is because the people writing these articles have no idea what they are talking about. You can't make a mouse look like an elephant, unless you are dealing with waves much longer than an elephant, in which case that would be like making a baseball look like an elephant sized baseball, and you wouldn't be able to tell the difference between the balls or mice or elephants. Only the size of the shadow would have relevance.

Metamaterials can only cloak objects smaller than the wavelength of light you are dealing with. Once you start getting to half wavelength objects the cloaking turns to crap, and only works for a very very thin bandwidth. That wouldn't be very helpful for visible cloaking, because we see a wide range of wavelengths.

What metamaterials MAY be useful is radar cloaking. There are also applications useful for scientific instruments such as NSOM (Near-field Scanning Optical Microscope), in which you can cloak the probe so that you do not interfere with the light you are trying to measure.

Metamaterials are very interesting, but not for the layman. Move along.

Once you start getting to half wavelength objects the cloaking turns to crap, and only works for a very very thin bandwidth. That wouldn't be very helpful for visible cloaking, because we see a wide range of wavelengths.

So now we finally have a realistic explanation for the lack of interaction with alien life forms. They've all developed illusion cloaks to protect their spacecraft and planets and everything.
They look like paperclips and rubber bands. And chapstick. That's why they're always disappearing and re-appearing.

Why the thing about pencil necks anyway? Does anyone actually WANT huge trapezius muscles, making them look like a smaller, less attractive version of The Hulk? Honestly, I see some guys at the gym who've built up their traps and they look fugly compared to the guys with decent balanced musculature. If you're going to insult nerd physique, at least aim your nasty remarks at the pidgeon chest, cooked spaghetti arms, scrawny legs or perma-keyboard hunch.

I remember fondly taping Dr. Demento in my teens (because I couldn't stay up that late), and Freddie Blassie was one of my favorite artists. Thanks for the memory. And to your other responder: "Pencil Neck Geek" was a song of his. I also recall Ogden Edsel's "Dead Puppies" (aren't much fun); and the good Doctor himself's "Shaving Cream".

It is not unreasonable to surmise that if we are able to develop this kind of technology (big if...) prior to developing reasonable technologies for enabling interstellar travel (whether some kind of suspended animation, long term survival technologies, or "warp drive"), then other civilizations may have as well. Thus it follows that any civilization with the technology to visit us would likely have the technology to observe us while remaining unobserved.

The summary is bad enough, talking about invisibility cloaks as if they actually exist. This and the prior work by the team are nothing more than computer models. I'm not discounting the importance of the research, just the way in which it's framed. We don't have such cloaks yet and likely won't for a long time.

Actually, rudimentary invisibility cloaks do exist [wikipedia.org]. The illusion cloak presented is a computer model showing that it's theoretically possible, but I agree that it should probably be phrased as "it may be possible that..." rather than as "hay gusy look wut i did".

Acording to the article, "The trick is to create a material in which the permittivity and permeability are complementary to the blah, blah, blah"
In other words the creation of a material that doesn't (or cannot in our universe) exist.
IMHO, a work of science fiction expressed in the language of mathematics.

IMO, a theory is not news. Especially with something like this, which just screams out "pics plz!". A Youtube video of it being thrown over the object or something would at least be an attempt to back it up, even though it's easily faked.

You know that it does not work that way, do you? I hope... or else I really do not know what you are? Because everybody knows that there are no girls on the net. And well, if you were a guy... Have you changed your underpants recently (last two decades)? ^^

True, but the invisibility cloak, at least, exists [howstuffworks.com]. If you moved your 'painting' around on the wall and it acted as a window into a larger scene, it would indeed be like this cloak.

As for the black hole thing, I presume that the red matter has to be heated to a certain temperature in order to 'detonate'. The fact that the planet's core is probably no hotter than the capsule would become on impact is a mere technicality and the big drill was cool, ok?:P

I'm at a loss to understand why the release of pictures is so important. Everyone with a grain of common sense *knows* it's been happening, and probably a lot worse at various worldwide CIA invisible detainment facilities.

Seems like just another media quest for ratings, "now with *exclusive" 1.3 megapix cellphone pictures of some brown person hung upside down".

What bothers me is more the fact that they took the pictures in the first place ? Official records of illegal activities ? Mementoes for someone's mi